Reliable and efficient compression systems have been developed and are used in a myriad of industrial processes (e.g., petroleum refineries, offshore oil production platforms, and subsea process control systems). There is, however, an ever-increasing demand for smaller, lighter, and more compact compression systems. Accordingly, compact motor-compressors that incorporate compressors directly coupled with high-speed electric motors have been developed. Conventional compact motor-compressors may combine a high-speed electric motor with a compressor, such as a centrifugal compressor, in a single, hermetically-sealed housing. In compact motor-compressors, the high-speed electric motor may operate in a process fluid contained in the housing, which may be maintained at a pressure from about 1 megapascal (MPa) to about 30 MPa. To deliver an electrical current across a pressure boundary of the housing and power the high-speed electric motor, high-voltage penetrators (HVPs) are often utilized. In topside or terrestrial (e.g., ground based) environments with ambient air external conditions, the HVPs may be contained in a pipe section extending from the sealed housing. These pipe sections, however, are neither practical nor adequate for the larger and more complex HVPs required in subsea environments.
In view of the foregoing, compact motor-compressors used in subsea environments may often include a terminal assembly or terminal box in lieu of the pipe section to couple with the HVPs. The terminal assembly may be mounted on the sealed housing and configured to couple with one or more HVPs. The HVPs may be configured to receive an electrical current from a sea- or land-based power source and transmit the electrical current to stator windings of the high-speed electric motor. In conventional compact motor-compressors, insulated, flexible cables may often be utilized to transmit the electrical current from the HVPs to the stator windings of the high-speed electric motor. The flexible cables, however, may be exposed to the process fluid contained in the housing, thereby resulting in the diffusion of the process fluid into the insulation thereof. In some cases, the process fluid may diffuse through the insulation and contact the conductive cables contained therein. During rapid gas decompression events, the process fluid contained in the flexible cables may depressurize and rapidly expand within the flexible cables, thereby compromising the structural integrity of the insulation. In some cases, the depressurization and rapid discharge of the process fluid may cause the insulation to rupture, thereby exposing the conductive elements contained therein.
What is needed, then, is an improved system and method for transmitting electrical power from a high-voltage penetrator to a motor of a compact motor-compressor.